Microsoft has disclosed just which limitations Windows Phone 'Tango' will have on low-end devices (256MB RAM). It's pretty hefty - most importantly, the ability to 'multitask' has been disabled. Aren't there more powerful unlimited Android phones out there? What's the point of all this?

This only works if the app properly handles that.
Android has the same API, but lots of app doesn't bother to support it. The result - you go back to an app to only realize your (saved game, document, web page, whatever) is gone, and be presented a launch screen.

Lots of apps had this problem in pre Mango. This will come back in Tango.